Most people don’t know where most of our products come from – what raw materials are used, how they are manufactured, etc. That makes it very hard to judge what is and is not environmentally friendly.
A few years ago some analysis revealed that a holistic assessment of ethanol’s environmental footprint from planting and harvesting through the point of burning it as a fuel in automobiles might be worse than the same consideration for gasoline. The farming, refining and transportation end of the businesses are also relevant. And as it burns it releases the same CO2 into the atmosphere at almost the same levels on a per-mile basis.
The same is true of many other products. That’s why I wasn’t surprised by the news that plastic grocery bags could be better for the environment than organic cotton ones.
That news came last spring from a study conducted by the Danish Environmental Protection Agency (DEPA). They measured the environmental impact of the standard plastic bag against “the organic lifecycle of seven common materials used for shopping bags…along 16 different environmental parameters, including climate impact, ozone impact, human and environmental toxicity and water use.”
According to the DEPA spokesperson, “The results showed that plastic bags made out of ‘LDPE plastic’, like the ones found in grocery stores, have by far the lowest impact on the environment. The biggest environmental impact was assigned to the organic cotton bag; it has to be used at least 149 times to offset its climate impact, compared to 43 times for a regular paper bag.” Note that people often buy the “organic” cotton believing they are doing the environment a favor.
At the end of the report, they recommended that any bag should be reused as many times as possible, for example, using the plastic grocery bags to line small trash cans. Note that if they were reused even once, would they be almost 300 times environmentally friendlier than an organic cotton bag?
But it doesn’t end there! Remember those reports earlier this month about the researchers at the Helsinki-Vantaa Airport, the main airport in Finland, finding that the place most filled with germs and bacteria was not the toilet seats but the trays used in the pre-flight screening process? They were teeming with disease-causing viruses. The same can be true of reusable cloth grocery bags and shoppers don’t realize that danger or guard against it.
As the Chicago Tribune reports: “Most shoppers -- 97%, in fact -- reported that they do not regularly, if ever, wash the bags.” About 75% report that they do not use separate bags for meats and for vegetables, while almost one-third use the same bags for other non-food items.
When they tested a sample of the bags (84) for bacteria, they found some contamination in all but one. The full report can be found at Assessment of the Potential for Cross Contamination of Food Products by Reusable Shopping Bags.
"It is estimated that there are about 76,000,000 cases of foodborne illness in the United States every year. Most of these illnesses originate in the home from improper cooking or handling of foods. Reusable bags, if not properly washed between uses, create the potential for cross-contamination of foods.” And if they must be washed between uses, that further adds to their environmental impact by water use, and it shortens their life.
So while some cities and states are moving to ban the bags, they are not considering all the diverse factors that go into the problem. It’s pretty typical of legislators to pass laws that address a surface problem to make them and their constituents feel good, while ignoring many details that might lead to an opposite conclusion.